Messi Biology states that Polyvinyl Chloride (PVC), as one of the largest volume general-purpose plastics globally, is widely applied in swimming pool liners, chemical piping, water treatment equipment, and medical consumables due to its low cost, excellent processability, and corrosion resistance. However, PVC is prone to aging and failure in chlorine-containing environments—chlorine disinfectants, industrial chlorinated wastewater, or active chlorine in seawater can accelerate the degradation of PVC molecular chains, leading to material embrittlement, discoloration, and a plummet in mechanical properties. Magnesium Carbonate, an eco-friendly inorganic material, is becoming the key to solving the challenge of PVC chlorine resistance, safeguarding its stable application in chlorinated environments.
The ability of Magnesium Carbonate to meet PVC’s chlorine resistance requirements stems from its unique physicochemical properties. It is a white crystalline powder with excellent dispersibility, thermal stability, and weak alkalinity. During the PVC processing stage, it blends uniformly with components such as resin and plasticizers without affecting the material’s molding process or basic performance. More critically, its weak alkalinity and chlorine capturing ability form a precise defense against PVC’s shortcomings regarding chlorine resistance.
In the production of PVC products, Magnesium Carbonate functions primarily through compounding. During production, a 2%-6% proportion of Magnesium Carbonate powder is fed into a mixer along with PVC resin, plasticizers, stabilizers, and other raw materials. After high-temperature melt mixing, the material is shaped through processes such as extrusion, injection molding, or calendering. When PVC products come into contact with a chlorine-containing environment, Magnesium Carbonate initiates “chemical protection”: its weak alkalinity neutralizes acidic substances generated by chlorine reactions, inhibiting the dehydrochlorination degradation reaction of PVC molecular chains—which is the core cause of aging in chlorine environments. Simultaneously, Magnesium Carbonate actively captures active chlorine free radicals, converting them into stable chlorides, thereby preventing chlorine molecules from attacking sensitive structures in the PVC molecular chain and delaying the aging process.
Beyond chemical protection, Magnesium Carbonate can also construct a “physical barrier.” Once uniformly dispersed within the PVC matrix, it fills the voids between resin molecules, improving the structural density of the material and reducing the permeation rate of active chlorine. Furthermore, the high thermal stability of Magnesium Carbonate reduces the risk of thermal degradation during PVC processing, further enhancing the overall stability of the product and forming a dual protection system of “chemical inhibition + physical barrier.”
Precise control of the addition amount is crucial to guaranteeing results: insufficient addition leads to inadequate chlorine protection, while excessive addition may affect the flexibility and processing fluidity of the PVC. PVC products modified with Magnesium Carbonate can see a 4-6 fold increase in chlorine resistance. Even after long-term immersion in chlorinated pool water or use in chlorinated chemical media, they maintain good toughness and structural integrity, with a service life extended by 2-3 times.
Today, as demands for chlorine-resistant materials upgrade in industries such as water treatment, chemical engineering, and swimming pool facilities, Magnesium Carbonate has become the preferred material for PVC chlorine-resistance modification due to its advantages of being eco-friendly, efficient, and cost-controllable. This common inorganic compound has not only broken through the bottleneck of PVC application in chlorine environments but also expanded the application boundaries of PVC, providing a more reliable and durable material choice for industrial production and daily life.